The Emperors force lighting was blue.
Although yes the effect did look similar but that's because it's lighting.
Lightning looks like lightning and other than MAKING IT GREEN, lightning is going to continue to look like lightning most of the time.
I've seen shit about Harry Potter Wands vs. light sabres elsewhere on and off.
Light sabres come in a lot of colours including purple.
George Lucas can try to patent lightning if he wants to, but frankly he'll just end up being treated like the last emperor of Japan or a 20-something Michael Jackson.
I don't see you complaining that what Theodora had going on throwing fireballs reminded you or Backdraft or Ladder 49.